Zhang Qinhui, Zhang Xinxin, Yang Yuchun, Xu Lianfeng, Feng Jian, Wang Jingyuan, Tang Yongsheng, Pei Xiaona, Zhao Xiyang
State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, China.
College of Forestry and Grassland, Jilin Agricultural University, Changchun, China.
Front Plant Sci. 2022 Jun 30;13:931578. doi: 10.3389/fpls.2022.931578. eCollection 2022.
is a native tree species in Northeast China. Due to habitat destruction and human disturbance, its population size has sharply decreased. Currently, information on molecular markers of is limited and cannot meet the needs of germplasm resource evaluation and molecular marker-assisted breeding of . Based on transcriptomic data from three tissues (leaves, bark, and fruit pericarp), we developed expressed sequence tag-simple sequence repeats (EST-SSRs) for , and 15 polymorphic EST-SSR primers were initially selected. The average number of alleles (), expected heterozygosity (), and the polymorphic information content () at different loci were 18.27, 0.670, and 0.797, respectively. Population genetic diversity analysis revealed that the average , and Shannon information indices () for 15 populations were 6.993, 0.670, and 1.455, respectively. Among them, population Hunchun exhibited the highest genetic diversity ( = 7.933, = 0.723, and = 1.617), while population Heihe exhibited the lowest genetic diversity ( = 4.200, = 0.605, and = 1.158). STRUCTURE analysis, neighbor-joining method cluster analysis, and principal coordinate analysis showed that the 343 individuals of from 15 populations were clustered into three categories. Category 1 (green) had 147 individuals from eight populations in Qingyuan, Caohekou, Jian, Ningan, Yongji, Baishishan, Helong, and Maoershan; category 2 (blue) had 81 individuals from three populations in Hulin, Boli, and Sanchazi; and category 3 (red) had 115 individuals from four populations in Heihe, Hunchun, Fangzheng, and Liangshui. Analysis of molecular variance (AMOVA) showed that genetic variations among and within individuals accounted for 16.22% and 21.10% of the total genetic variation, respectively, indicating that genetic variations within populations were greater than genetic variations among populations. The average genetic differentiation coefficient () and gene flow () between different populations were 0.109 and 4.063, respectively, implying moderate levels of genetic differentiation and gene flow. Based on the genetic diversity characteristics of different populations, we proposed various genetic conservation strategies for .
是中国东北地区的本土树种。由于栖息地破坏和人为干扰，其种群规模急剧减少。目前，关于该树种的分子标记信息有限，无法满足其种质资源评价和分子标记辅助育种的需求。基于来自三个组织（叶片、树皮和果实果皮）的转录组数据，我们开发了该树种的表达序列标签简单序列重复（EST-SSR），并初步筛选出15对多态性EST-SSR引物。不同位点的平均等位基因数（）、期望杂合度（）和多态信息含量（）分别为18.27、0.670和0.797。种群遗传多样性分析表明，15个种群的平均、香农信息指数（）分别为6.993、0.670和1.455。其中，珲春种群的遗传多样性最高（ = 7.933， = 0.723， = 1.617），而黑河种群的遗传多样性最低（ = 4.200， = 0.605， = 1.158）。STRUCTURE分析、邻接法聚类分析和主坐标分析表明，来自15个种群的343个该树种个体被聚类为三类。第一类（绿色）有来自清源、草河口、吉安、宁安、永吉、白石山、和龙、帽儿山八个种群的147个个体；第二类（蓝色）有来自虎林、勃利、三岔子三个种群的81个个体；第三类（红色）有来自黑河、珲春、方正、凉水四个种群的115个个体。分子方差分析（AMOVA）表明，个体间和个体内的遗传变异分别占总遗传变异的16.22%和21.10%，表明种群内的遗传变异大于种群间的遗传变异。不同种群间的平均遗传分化系数（）和基因流（）分别为0.109和4.063，意味着遗传分化和基因流处于中等水平。基于不同种群的遗传多样性特征，我们提出了该树种的各种遗传保护策略。
